July 31 - Tthe Allies launch a renewed assault on German lines in the Flanders region of Belgium, in the much-contested region near Ypres, during World War I. The attack begins more than three months of brutal fighting, known as the Third Battle of Ypres.

April 9-April 12 - World War I: Canadian troops win the Battle of Vimy Ridge.

April 16 - The Nivelle Offensive commences.

The Nivelle Offensive was a 1917 Allied attack on the Western Front in World War I. Promised as the assault that would end the war within 48 hours, with casualties expected of around 10,000 men, it failed on both counts.[citation needed] It was a three-stage plan. The high levels of casualties rapidly caused unrest throughout the French Army and led to a change of leadership of the French Army.

This was a preliminary attack by the British and Dominion First, Third and Fifth Armies at Arras. See Battle of Arras (1917) and Vimy Ridge.

French assault at Chemin des Dames ridge. See Second Battle of the Aisne (also known as the Third Battle of Champagne).

A linkup of the British and Dominion and French armies, having broken through the German lines. This didn't happen.

When Robert Nivelle took over from Joseph Joffre as French Commander-in-Chief in December 1916 after the costly fighting at Verdun and the Somme, he argued that a massive onslaught on German lines would bring French victory in 48 hours. The plan was put into action on 16 April 1917 after support from France's Prime Minister, despite strong disapproval from other high-ranking officials.

The Nivelle offensive was a huge and costly undertaking, involving around 1.2 million troops and 7,000 artillery pieces on a broad front between Royle and Reims. Its main focus was a massive assault on the German positions along the Aisne river, in the Second Battle of the Aisne. From the start, the plan, which had been in development since December 1916, was plagued by delays and information leaks. By the time it went into action in April 1917, the plans were well known to the German army, who took appropriate defensive measures.

The offensive achieved very little in the way of territorial gain, nowhere near the 48-hour breakthrough envisaged. In the aftermath of its end on 9 May 1917, Nivelle was sacked, ending his career. There were over 187,000 French casualties alone, sparking widespread mutiny in the French army, including one famous incident where, as the offensive was winding down, the French 2nd Division arrived on the battlefield, drunk and without weapons

May 27 - Over 30,000 French troops refuse to go to the trenches in Missy-aux-Bois.
Almost immediately after the failure of the offensive of 16 April, there began what its commanders would admit to be 'acts of collective indiscipline' and what historians have called 'the mutinies of 1917.'

"The general mood of those involved - and they comprised soldiers in fifty-four
divisions, almost half the army - was one of reluctance, if not refusal, to take part in fresh attacks but also of patriotic willingness to hold the line against attacks by the enemy. There were also specific demands: more leave, better food, better treatment for soldiers' families, an end to 'injustice' and 'butchery.' ... The demands were often linked to those of participants in civilian strikes, [where French citizens] complained that 'While the people have to
work themselves to death to scrape a living, the bosses and the big industrialists are growing fat.'

"As the crisis deepened - and five phases have been identified, from scattered outbreaks in April to mass meetings in May, and hostile encounters June, followed by an attenuation of dissent during the rest of the year - [General Philippe Petain] set in train a series of measures designed to contain it and return the army to moral well-being. He promised ampler and more
regular leave. He also implicitly promised an end, for a time at least, to attacks, not in so many words, for that would have spelled an end to the status of France as a war-waging power, but by emphasising that the troops would be rested and retrained. ...

"While the front was being reorganised for these new tactics, the army's officers, with Petain's approval, were attempting to win back the men's obedience by argument and encouragement. 'No rigorous measures must be taken,' wrote the commander of the 5th Division's infantry. 'We must do our best to dilute the movement by persuasion, by calm and by the authority of the officers known by the men, and acting above all on the good ones to bring
the strikers to the best sentiments.' His divisional commander agreed: 'we cannot think of reducing the movement by rigour, which would certainly bring about the irreparable.'

"Nevertheless, the 'movement' - indiscipline, strike or mutiny - was not put down without resort to force. Both high command and government, obsessed by a belief that there had been 'subversion' of the army by civilian anti-war agitators, devoted a great deal of effort to identifying ringleaders, to bringing them to trial and to punishing them. There were 3,427 courts-martial, by which 554 soldiers were condemned to death and forty-nine actually shot. Hundreds of others, though reprieved, were sentenced to life imprisonment. A particular feature of the legal process was that those sent for trial were selected by their own officers and NCOs, with the implicit consent of the rank and file.

"Superficially, order was restored within the French army with relative speed. ... In general, however, the objects of the mutinies had been achieved. The French army did not attack anywhere on the Western Front, of which it held two-thirds, between June 1917 and July 1918, nor did it conduct an 'active' defence of its sectors. The Germans, who had inexplicably failed to detect the crisis of discipline on the other side of no man's land, were content to accept their enemy's passivity, having business of their own elsewhere, in Russia, in Italy and against the British."

June 1 - A French infantry regiment seizes Missy-aux-Bois and declares an anti-war military government. Other French army troops soon apprehend them.

June - "...returning a little drunk from a night out with a friend, he [Adolf Hitler] got frisky with Charlotte [Charlotte Lobjoie, was 16 when Hitler, who was a corporal serving with German forces in France in World War I,]. In March of the next year, a son [Jean-Marie Loret 1918-1985] was born." [This story is contested but the latest research shows it is likely.]

October 15 - World War I: At Vincennes outside of Paris, Dutch dancer Mata Hari is executed by firing squad for spying for Germany.

Execution of Mata Hari

Henry Wales was a British reporter who covered the execution. His story begins as Mata Hari is awakened in the early morning of 15 October. She had made a direct appeal to the French president for clemency and was expectantly awaiting his reply:

The first intimation she received that her plea had been denied was when she was led at daybreak from her cell in the Saint-Lazare prison to a waiting automobile and then rushed to the barracks where the firing squad awaited her. Never once had the iron will of the beautiful woman failed her. Father Arbaux, accompanied by two sisters of charity, Captain Bouchardon, and Maitre Clunet, her lawyer, entered her cell, where she was still sleeping - a calm, untroubled sleep, it was remarked by the turnkeys and trusties. The sisters gently shook her. She arose and was told that her hour had come. 'May I write two letters?' was all she asked. Consent was given immediately by Captain Bouchardon, and pen, ink, paper, and envelopes were given to her. She seated herself at the edge of the bed and wrote the letters with feverish haste. She handed them over to the custody of her lawyer. Then she drew on her stockings, black, silken, filmy things, grotesque in the circumstances. She placed her high-heeled slippers on her feet and tied the silken ribbons over her insteps. She arose and took the long black velvet cloak, edged around the bottom with fur and with a huge square fur collar hanging down the back, from a hook over the head of her bed. She placed this cloak over the heavy silk kimono which she had been wearing over her nightdress. Her wealth of black hair was still coiled about her head in braids. She put on a large, flapping black felt hat with a black silk ribbon and bow. Slowly and indifferently, it seemed, she pulled on a pair of black kid gloves. Then she said calmly: 'I am ready.' The party slowly filed out of her cell to the waiting automobile. The car sped through the heart of the sleeping city. It was scarcely half-past five in the morning and the sun was not yet fully up. Clear across Paris the car whirled to the Caserne de Vincennes, the barracks of the old fort which the Germans stormed in 1870. The troops were already drawn up for the execution. The twelve Zouaves, forming the firing squad, stood in line, their rifles at ease. A subofficer stood behind them, sword drawn. The automobile stopped, and the party descended, Mata Hari last. The party walked straight to the spot, where a little hummock of earth reared itself seven or eight feet high and afforded a background for such bullets as might miss the human target. As Father Arbaux spoke with the condemned woman, a French officer approached, carrying a white cloth. 'The blindfold,' he whispered to the nuns who stood there and handed it to them. 'Must I wear that?' asked Mata Hari, turning to her lawyer, as her eyes glimpsed the blindfold. Maitre Clunet turned interrogatively to the French officer. 'If Madame prefers not, it makes no difference,' replied the officer, hurriedly turning away. Mata Hari was not bound and she was not blindfolded. She stood gazing steadfastly at her executioners, when the priest, the nuns, and her lawyer stepped away from her. The officer in command of the firing squad, who had been watching his men like a hawk that none might examine his rifle and try to find out whether he was destined to fire the blank cartridge which was in the breech of one rifle, seemed relieved that the business would soon be over. A sharp, crackling command and the file of twelve men assumed rigid positions at attention. Another command, and their rifles were at their shoulders; each man gazed down his barrel at the breast of the woman which was the target. She did not move a muscle. The underofficer in charge had moved to a position where from the corners of their eyes they could see him. His sword was extended in the air. It dropped. The sun - by this time up - flashed on the burnished blade as it described an arc in falling. Simultaneously the sound of the volley rang out. Flame and a tiny puff of greyish smoke issued from the muzzle of each rifle. Automatically the men dropped their arms. At the report Mata Hari fell. She did not die as actors and moving picture stars would have us believe that people die when they are shot. She did not throw up her hands nor did she plunge straight forward or straight back. Instead she seemed to collapse. Slowly, inertly, she settled to her knees, her head up always, and without the slightest change of expression on her face. For the fraction of a second it seemed she tottered there, on her knees, gazing directly at those who had taken her life. Then she fell backward, bending at the waist, with her legs doubled up beneath her. She lay prone, motionless, with her face turned towards the sky. A non-commissioned officer, who accompanied a lieutenant, drew his revolver from the big, black holster strapped about his waist. Bending over, he placed the muzzle of the revolver almost - but not quite - against the left temple of the spy. He pulled the trigger, and the bullet tore into the brain of the woman. Mata Hari was surely dead.

January 19 - Silvertown explosion: A blast at a munitions factory in London kills 73 and injures over 400. The resulting fire causes over £2,000,000 worth of damage.

January 26 - The sea defences at the English village of Hallsands are breached, leading to all but one of the houses becoming uninhabitable.

February 24 - World War I: United States ambassador to the United Kingdom Walter H. Page is given the Zimmermann Telegram, in which Germany offers to give the American Southwest back to Mexico, if Mexico declares war on the United States.

June 13 - World War I: The first major German bombing raid on London leaves 162 dead and 432 injured.

July 17 - King George V of the United Kingdom issues a proclamation, stating that thenceforth the male line descendants of the British Royal Family will bear the surname Windsor, vice the Germanic bloodline of House of Saxe-Coburg and Gotha, which is an offshoot of the historic (800+ years) House of Wettin.

May 23 - A month of civil violence in Milan, Italy ends after the Italian army forcefully takes over the city from anarchists and anti-war revolutionaries. Fifty people are killed and 800 people are arrested.

July 6 - A conscription crisis in Canada leads to passage of the Military Service Act.

July 25 - Sir Thomas Whyte introduces the first income tax in Canada as a "temporary" measure (lowest bracket is 4% and highest is 25%).

December 6 - The Halifax Explosion occurred on Thursday, when the city of Halifax, Nova Scotia, Canada, was devastated by the huge detonation of a French cargo ship, fully loaded with wartime explosives, that had accidentally collided with a Norwegian ship in "The Narrows" section of the Halifax Harbour. Approximately 2,000 people (mostly Canadians) were killed by debris, fires, or collapsed buildings, and it is estimated that over 9,000 people were injured. This is still one of the world's largest man-made, conventional explosions to date.

Since the explosion occurred in the winter, the blast caused stoves, lamps and furnaces to tip or spill, spreading fires throughout the devastation, particularly in Halifax's North End, leaving entire streets on fire. Fuel reserves were high in preparation for the winter. Many people who had survived the blast were trapped in these fires. Problems were compounded as firemen from surrounding communities arrived and were unable to use their equipment, as hoses and hydrants were not standardized across communities or regions. Winds cooperated, and firemen, soldiers and other volunteers had most of the fires contained by evening.

Some 1.32 km² (325 acres) of Halifax was destroyed, essentially leaving a 1.6 kilometre (1 mi) radius around the blast site uninhabitable. Many people who had gathered around the ship either to help or watch were amongst those killed in the blast, or were subsequently hit by the resulting tsunami. Others who had been watching from the windows of their homes and businesses were either killed instantly or severely injured by the flying glass as their windows shattered inwards.

January 30 - Pershing's troops in Mexico begin withdrawing back to the United States. They reach Columbus, Ohio February 5.

February 5 - The constitution of Mexico is adopted.

The Political Constitution of the United Mexican States of 1917 was signed and is the current constitution of Mexico. It was drafted in Santiago de Querétaro by a Constitutional Convention during the Mexican Revolution. It was approved by the Constitutional Congress on February 5, 1917, with Venustiano Carranza serving as the first president under its terms.

Although only supporters of the Plan of Guadalupe were welcomed to the constitutional convention, these delegates were swayed by radicals who held to many of the ideals of nineteenth-century liberalism. The most important articles, 3, 27, and 123, displayed profound changes in Mexican political philosophy that would help frame the political and social backdrop for the rest of the century.

March 11 - Mexican Revolution: Venustiano Carranza is elected president of Mexico; the United States gives de jurerecognition of his government.

January 11 - German saboteurs set off the Kingsland Explosion at Kingsland, NJ (now Lyndhurst, NJ), one of the events leading to U.S. involvement in World War I.

January 25 - The Danish West Indies is sold to the United States for $25 million.

January 25 - An anti-prostitution drive in San Francisco attracts huge crowds to public meetings. At one meeting attended by 7,000 people, 20,000 are kept out for lack of room. In a conference with Rev. Paul Smith, an outspoken foe of prostitution, 300 prostitutes make a plea for toleration, explaining they had been forced into the practice by poverty. When Smith asks if they will take other work at $8 to $10 a week, the ladies laugh derisively, which loses them public sympathy. The police close about 200 houses of prostitution shortly thereafter.

January 28 - The United States ends its search for Pancho Villa.

February 3 - World War I: The United States breaks off diplomatic relations with Germany.

March 1 - The U.S. government releases the plaintext of the Zimmermann Telegram to the public.

March 2 - The enactment of the Jones Act grants Puerto Ricans United States citizenship.

March 31 - The United States takes possession of the Danish West Indies, which become the US Virgin Islands, after paying $25 million to Denmark.

April 2 - World War I: U.S. President Woodrow Wilson asks the U.S. Congress for a declaration of war on Germany.

July 1 - A labor dispute ignites a race riot in East St. Louis, Illinois, which leaves 250 dead.

July 12 - The Phelps Dodge Corporation deports over 1,000 suspected IWW members from Bisbee, Arizona.

July 28 - The Silent Protest is organized by the NAACP in New York to protest the East St. Louis Riot of July 2, as well as lynchings in Texas and Tennessee. Thousands of black people walked in silence down Fifth Avenue in New York City

August - The Green Corn Rebellion, an uprising by several hundred farmers against the World War I draft, takes place in central Oklahoma.

August 3 - The New York Guard is founded.

October 19 - Love Field in Dallas, Texas is opened.

November 15 - In the United States, a "Night of Terror" results in the death of several influential suffragettes.

November 24 - In Milwaukee, Wisconsin, 9 members of the Milwaukee Police Department are killed by a bomb, the most fatal single event in U.S. police history until the September 11, 2001 attacks.

December 26 - United States president Woodrow Wilson uses the Federal Possession and Control Act to place most U.S. railroads under the United States Railroad Administration, hoping to more efficiently transport troops and materials for the war effort.

Italian immigrant Antonio Pasin started building wooden toy wagons eventually to be named Radio Flyers which have dominated the toy wagon industry in the U.S. for over 90 years.

The Telefunken Wireless Tower constructed by Nikola Tesla was seized and blown up with dynamite for scrap by the Marines, owing to fears that German spies were using it and that it could be used as a landmark for German submarines

August - Tesla, in August 1917, first established principles of frequency and power level for the first primitive radar units

Gross industrial production in 1917 had decreased by over 36 percent from what it had been in 1916. In the autumn, as much as 50 percent of all enterprises were closed down in the Urals, the Donbas, and other industrial centers, leading to mass unemployment. At the same time, the cost of living increased sharply. The real wages of the workers fell about 50 percent from what they had been in 1913. Russia's national debt in October 1917 had risen to 50 billion rubles. Of this, debts to foreign governments constituted more than 11 billion rubles. The country faced the threat of financial bankruptcy.

March 8 - (N.S.) (February 23, O.S.) - The Russian February Revolution begins with the overthrow of the Tsar. Women calling for bread in Petrograd start riots, which spontaneously spread throughout the city.

In September and October 1917, there were strikes by the Moscow and Petrograd workers, the miners of the Donbas, the metalworkers of the Urals, the oil workers of Baku, the textile workers of the Central Industrial Region, and the railroad workers on 44 different railway lines. In these months alone more than a million workers took part in mass strike action. Workers established control over production and distribution in many factories and plants in a social revolution.

By October 1917 there had been over four thousand peasant uprisings against landowners. When the Provisional Government sent out punitive detachments it only enraged the peasants. The garrisons in Petrograd, Moscow, and other cities, the Northern and Western fronts, and the sailors of the Baltic Fleet in September openly declared through their elected representative body Tsentrobalt that they did not recognize the authority of the Provisional Government and would not carry out any of its commands.

The period of competition for authority ended in late October when Bolsheviks routed the ministers of the Provisional Government in the events known as the October Revolution, and placed power in the hands of the soviets, or "workers' councils," which they largely controlled.

October 23 [O.S. 10 October], the Bolsheviks' Central Committee voted 10-2 for a resolution saying that "an armed uprising is inevitable, and that the time for it is fully ripe.

November 5 [O.S. 23 October] 1917, Bolshevik leader Jaan Anvelt led his leftist revolutionaries in an uprising in Tallinn, the capital of the Autonomous Governorate of Estonia.

November 6 - Militants from Trotsky's committee join with trusty Bolshevik soldiers to seize government buildings and pounce on members of the provisional government.

November 7 - October Revolution: The workers of Petrograd in Russia, led by the Bolshevik leader Vladimir Lenin, attack the Kerensky Provisional Government ( Julian Calendar shows an October 25 date).

November 23 - The Bolsheviks release the full text of the previously secret Sykes-Picot Agreement in Izvestia and Pravda; it is subsequently printed in the Manchester Guardian on November 26.

November 28 - The Bolsheviks offer peace terms to the Germans.

November 29 - Don Cossacks declare the Don Republic, which lasts two weeks.